1. Field of the Invention
The present invention relates to a connector for connecting a first connecting cable connected to one end of a socket and a second connecting cable connected to one end of a plug, through engagement between the socket and the plug.
2. Description of the Related Art
In electric apparatuses or the like, there are often employed a power cable for power supply and a signal cable for signal transmission. When such power cable or signal cable is physically extended or signal is transmitted to another electric apparatus, cable-to-cable connection is often provided. In such connection, there is often employed a connector configured to realize the desired object through engagement between a socket and a plug, with a cable being attached to one end of the socket and the other cable being attached to one end of the plug. Some examples of connector of this type are known from patent documents identified below.
Japanese Patent Application “Kokai” No. 10-162896 (corresponding to the U.S. Pat. No. 5,984,705) discloses a connector including a pair of connector housings engageable to each other and a locking means for locking the pair of connector housings under their engaged condition.
Japanese Patent Application “Kokai” No. 11-135190 discloses a water-resistant connector consisting of a receptacle-side connector and a plug-side connector. The receptacle-side connector includes an engaging portion that is formed integrally at an outer peripheral portion of the opened end of an insertion hole of the connector. This engaging portion includes an annular engaging member and a supporting member. The annular engaging member is formed coaxially with and disposed with a predetermined distance from the opened end outer peripheral portion. The annular engaging member is formed thin and has a same width as the opened end outer peripheral portion. The supporting member is configured for interconnecting the outer peripheral portion and an inner peripheral face of the annular engaging member. Further, the plug-side connector includes an inserting projection to be loosely inserted into the insertion hole. An O-ring is non-withdrawbly retained on the outer peripheral portion of the inserting projection so that the connector, when inserted, is compressively deformed between the inner peripheral face of the insertion hole and the outer peripheral face of the inserting projection, thus providing liquid-tight seal therebetween. Further, the plug-side connector includes an engaged portion to be non-withdrawbly retained to the annular engaging member.
Japanese Patent No. 3077696 (corresponding to U.S. Pat. No. 6,296,508) discloses a connector including a pair of connector housings which are formed cylindrical and coaxially engageable with each other upon relative axial advancement thereof. This connector includes a positioning means having a groove formed in one of the housings and a rib formed on the other housing. Upon establishment of engagement between the groove and the rib, the pair of housing connectors are restricted in their relative rotation in the peripheral direction and at the same time are allowed to move in the axial direction for mutual engagement. The connector further includes a guiding means for enabling relative rotation between the two connector housings substantially coaxially and peripherally, with no engagement between the groove and the rib.
Japanese Patent No. 3191909 (corresponding to U.S. Pat. No. 5,718,597) discloses a connector having an engagement guiding function. The connector includes a pair of connector housings to be engaged with each other. One of the housings includes a bush portion for receiving the other connector housing. And, at upper and lower and right and left peripheral walls of the bush member, there are provided inclined faces opposed to each other and opened with progressively increasing diameter in the respective engaging direction. End portions in the engaging direction of the adjacent inclined faces are located close to each other and guiding projections are provided at upper and lower and right and left peripheral walls of the other connector housing. Further, at the bottoms of the inclined face opposed thereto, there is formed a retaining hole for receiving the guiding projection.
However, in the case of the connector disclosed in Japanese Patent Application “Kokai” No. 10-162896 (corresponding U.S. Pat. No. 5,984,705), in the course of engagement between the pair of connector housings, if there exists an error between the positions of the locking means provided in the respective connector housings, the locking means are disabled from functioning. Therefore, there arises a need for effecting the alignment between the locking means with visual judgment.
Further, in the case of the water-resistant connector disclosed in Japanese Patent Application “Kokai” No. 11-135190, in the course of the engagement between the receptacle-side connector and the plug-side connector, there is a need for effecting the alignment with visual judgment, just like the locking means of Patent Document 1 above.
In the case of the connector disclosed in Japanese patent No. 3077696 (corresponding U.S. Pat. No. 6,296,508), engagement is possible without relying on visual judgment, by rotating the pair of connector housings in the peripheral direction, with pressing these housings against each other. However, since this rotation under pressure applies an excess stress to the connector housings, there is a need to form the connector housings with a strength sufficient to endure this stress.
Further, in the case of the connector having the engagement guiding function disclosed in Japanese patent No. 3191909 (corresponding U.S. Pat. No. 5,718,597), there is a need to form the guiding projection long enough to be capable of guiding even when one connector housing is displaced maximally in either direction relative to the other connector housing. For this reason, even if the pair of connector housings are engaged appropriately, the guiding projection will project prominently from the connector housing, so that there is a risk of this guiding projection being damaged as being inadvertently hooked with a component or object other than the connector.